Tottenham failed to fully capitalise on a defeat for Manchester City as they were held to a 1-1 draw by Blackpool, but Jermain Defoe's equaliser came as real relief for his former side West Ham, who could only draw at home to Blackburn.
Spurs knew a win could have taken them to within four points of Manchester City in fourth place, but fell behind in farcical circumstances at White Hart Lane. Michael Dawson handballed to concede a penalty in the second half and Heurelho Gomes saved from Charlie Adam, but within 70 seconds the goalkeeper fouled Gary Taylor-Fletcher to concede another spot-kick.
Adam scored his second attempt from 12 yards after 76 minutes and had seemingly put Blackpool on course for a vital three points. However, Jermain Defoe scored with a minute of normal time remaining. Spurs also saw Gareth Bale taken off on a stretcher following a poor challenge from Adam, with the PFA Player of the Year suffering a potentially serious ankle injury.
The result means Spurs are six points behind City with three games remaining, ahead of the meeting of the two clubs on Tuesday. Blackpool remain level with Wigan, and three points clear of bottom club West Ham, though out of the relegation zone on goal difference in 17th place.
City earlier left the door open for Tottenham or perhaps Liverpool to snatch a Champions League place after falling to a 2-1 defeat at Everton.
Although City could have been forgiven for having one mind on next week's FA Cup final, there was no sign of distraction early on as they created a glut of chances - so it was no surprise when Yaya Toure put them ahead on 30 minutes, the Ivorian latching onto David Silva's fine through ball before coolly slotting past Tim Howard.
City continued to impress at the start of the second period, but it was Everton who struck next, as former City player Sylvain Distin hammered in a header from Mikel Arteta's delivery on 65 minutes, leaving Roberto Mancini irate on the touchline.
And the Italian's mood worsened shortly after as Leon Osman, a diminuitive midfielder not known for his prowess in the air, climbed highest to nudge the Toffees ahead - and extend Mancini's record against Everton to zero points from four league games.
West Ham remain in grave danger of slipping through the relegation trapdoor after being held to a 1-1 draw by Blackburn Rovers at Upton Park. The Hammers are rooted to the bottom of the table, three points from safety with two games remaining, while Blackburn are three points away from 18th place.
Avram Grant's side made a promising start to the match, with Manuel da Costa having a header cleared off the line, but it was Rovers who took the lead on 12 minutes, Jason Roberts sliding in from six yards following a fine low cross from Brett Emerton.
After taking a while to settle down following the early setback, the Hammers found themselves in charge at the start of the second period - although, for all their pressure, most of their efforts were fizzing wide from long range. A strike from distance did creep in on 78 minutes, however, as Thomas Hitzlsperger lashed the ball in from 18 yards with an unstoppable first-time shot that left Paul Robinson motionless.
The Hammers had a golden chance to snatch the points with three minutes remaining, Robbie Keane somehow sidefooting wide from four yards out. The Hammers avoided defeat for the first time in six matches, but it looks unlikely that it will be enough to keep them in the league.
Wigan remain in 18th place, level with Blackpool, after a 1-1 draw against Aston Villa. The visitors, who had never lost at Villa Park in the league before kick-off, claimed a deserved lead on ten minutes as Charles N'Zogbia tapped in following fine approach work from Victor Moses. The hosts hit back almost immediately, however, with Ashley Young firing in a 25-yard free-kick that Ali Al-Habsi, diving low to his left, could not keep out.
Chances were at a premium during a tense second half, although Hugo Rodallega did go agonisingly close to seizing all three points for Wigan, who host West Ham next week in a relegation showdown.
Birmingham still have cause for concern at the bottom of the table following a 2-1 defeat at Newcastle. After an uneventful 35 minutes, Alex McLeish's side were plunged into chaos as half-time approached when Shola Ameobi found the back of the net from the spot, with the striker profiting from Liam Ridgewell's handball on the line - an offence which saw the Blues defender dismissed.
Before they could reach the sanctuary of the dressing room, Alex McLeish's side saw their plight deepen as Steven Taylor buried a header from a corner - but Lee Bowyer, formerly of Newcastle, halved the deficit prior to the interval with a deflected strike. In the second period, Sebastian Larsson spurned a golden chance to earn the visitors - who are three points away from the drop zone - a draw.
A 90th-minute own goal from Zat Knight earned Sunderland a 2-1 victory at Bolton Wanderers. An injury-ravaged Sunderland outfit, who had taken four points from 33 prior to the fixture, claimed a shock advantage on 44 minutes thanks to Bolo Zenden, who beat the offside trap before rounding Jussi Jaaskelainen and rolling into the empty net. The strike was the Black Cats' first on their travels for three months.
The visitors looked to have had their hearts broken when Ivan Klasnic equalised with five minutes remaining, before Knight bundled into his own net.